--- /dev/null
+/*
+ * counter/counter-api.h
+ *
+ * LTTng Counters API, requiring counter/config.h
+ *
+ * Copyright (C) 2020 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef _LTTNG_COUNTER_API_H
+#define _LTTNG_COUNTER_API_H
+
+#include <stdint.h>
+#include <limits.h>
+#include "counter.h"
+#include "counter-internal.h"
+#include <urcu/compiler.h>
+#include <urcu/uatomic.h>
+#include <lttng/bitmap.h>
+#include "../libringbuffer/getcpu.h"
+
+/*
+ * Using unsigned arithmetic because overflow is defined.
+ */
+static inline int __lttng_counter_add(const struct lib_counter_config *config,
+ enum lib_counter_config_alloc alloc,
+ enum lib_counter_config_sync sync,
+ struct lib_counter *counter,
+ const size_t *dimension_indexes, int64_t v,
+ int64_t *remainder)
+{
+ size_t index;
+ bool overflow = false, underflow = false;
+ struct lib_counter_layout *layout;
+ int64_t move_sum = 0;
+
+ if (caa_unlikely(lttng_counter_validate_indexes(config, counter, dimension_indexes)))
+ return -EOVERFLOW;
+ index = lttng_counter_get_index(config, counter, dimension_indexes);
+
+ switch (alloc) {
+ case COUNTER_ALLOC_PER_CPU:
+ layout = &counter->percpu_counters[lttng_ust_get_cpu()];
+ break;
+ case COUNTER_ALLOC_GLOBAL:
+ layout = &counter->global_counters;
+ break;
+ default:
+ return -EINVAL;
+ }
+ if (caa_unlikely(!layout->counters))
+ return -ENODEV;
+
+ switch (config->counter_size) {
+ case COUNTER_SIZE_8_BIT:
+ {
+ int8_t *int_p = (int8_t *) layout->counters + index;
+ int8_t old, n, res;
+ int8_t global_sum_step = counter->global_sum_step.s8;
+
+ res = *int_p;
+ switch (sync) {
+ case COUNTER_SYNC_PER_CPU:
+ {
+ do {
+ move_sum = 0;
+ old = res;
+ n = (int8_t) ((uint8_t) old + (uint8_t) v);
+ if (caa_unlikely(n > (int8_t) global_sum_step))
+ move_sum = (int8_t) global_sum_step / 2;
+ else if (caa_unlikely(n < -(int8_t) global_sum_step))
+ move_sum = -((int8_t) global_sum_step / 2);
+ n -= move_sum;
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ case COUNTER_SYNC_GLOBAL:
+ {
+ do {
+ old = res;
+ n = (int8_t) ((uint8_t) old + (uint8_t) v);
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ }
+ if (v > 0 && (v >= UINT8_MAX || n < old))
+ overflow = true;
+ else if (v < 0 && (v <= -UINT8_MAX || n > old))
+ underflow = true;
+ break;
+ }
+ case COUNTER_SIZE_16_BIT:
+ {
+ int16_t *int_p = (int16_t *) layout->counters + index;
+ int16_t old, n, res;
+ int16_t global_sum_step = counter->global_sum_step.s16;
+
+ res = *int_p;
+ switch (sync) {
+ case COUNTER_SYNC_PER_CPU:
+ {
+ do {
+ move_sum = 0;
+ old = res;
+ n = (int16_t) ((uint16_t) old + (uint16_t) v);
+ if (caa_unlikely(n > (int16_t) global_sum_step))
+ move_sum = (int16_t) global_sum_step / 2;
+ else if (caa_unlikely(n < -(int16_t) global_sum_step))
+ move_sum = -((int16_t) global_sum_step / 2);
+ n -= move_sum;
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ case COUNTER_SYNC_GLOBAL:
+ {
+ do {
+ old = res;
+ n = (int16_t) ((uint16_t) old + (uint16_t) v);
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ }
+ if (v > 0 && (v >= UINT16_MAX || n < old))
+ overflow = true;
+ else if (v < 0 && (v <= -UINT16_MAX || n > old))
+ underflow = true;
+ break;
+ }
+ case COUNTER_SIZE_32_BIT:
+ {
+ int32_t *int_p = (int32_t *) layout->counters + index;
+ int32_t old, n, res;
+ int32_t global_sum_step = counter->global_sum_step.s32;
+
+ res = *int_p;
+ switch (sync) {
+ case COUNTER_SYNC_PER_CPU:
+ {
+ do {
+ move_sum = 0;
+ old = res;
+ n = (int32_t) ((uint32_t) old + (uint32_t) v);
+ if (caa_unlikely(n > (int32_t) global_sum_step))
+ move_sum = (int32_t) global_sum_step / 2;
+ else if (caa_unlikely(n < -(int32_t) global_sum_step))
+ move_sum = -((int32_t) global_sum_step / 2);
+ n -= move_sum;
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ case COUNTER_SYNC_GLOBAL:
+ {
+ do {
+ old = res;
+ n = (int32_t) ((uint32_t) old + (uint32_t) v);
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ }
+ if (v > 0 && (v >= UINT32_MAX || n < old))
+ overflow = true;
+ else if (v < 0 && (v <= -UINT32_MAX || n > old))
+ underflow = true;
+ break;
+ }
+#if CAA_BITS_PER_LONG == 64
+ case COUNTER_SIZE_64_BIT:
+ {
+ int64_t *int_p = (int64_t *) layout->counters + index;
+ int64_t old, n, res;
+ int64_t global_sum_step = counter->global_sum_step.s64;
+
+ res = *int_p;
+ switch (sync) {
+ case COUNTER_SYNC_PER_CPU:
+ {
+ do {
+ move_sum = 0;
+ old = res;
+ n = (int64_t) ((uint64_t) old + (uint64_t) v);
+ if (caa_unlikely(n > (int64_t) global_sum_step))
+ move_sum = (int64_t) global_sum_step / 2;
+ else if (caa_unlikely(n < -(int64_t) global_sum_step))
+ move_sum = -((int64_t) global_sum_step / 2);
+ n -= move_sum;
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ case COUNTER_SYNC_GLOBAL:
+ {
+ do {
+ old = res;
+ n = (int64_t) ((uint64_t) old + (uint64_t) v);
+ res = uatomic_cmpxchg(int_p, old, n);
+ } while (old != res);
+ break;
+ }
+ }
+ if (v > 0 && n < old)
+ overflow = true;
+ else if (v < 0 && n > old)
+ underflow = true;
+ break;
+ }
+#endif
+ default:
+ return -EINVAL;
+ }
+ if (caa_unlikely(overflow && !lttng_bitmap_test_bit(index, layout->overflow_bitmap)))
+ lttng_bitmap_set_bit(index, layout->overflow_bitmap);
+ else if (caa_unlikely(underflow && !lttng_bitmap_test_bit(index, layout->underflow_bitmap)))
+ lttng_bitmap_set_bit(index, layout->underflow_bitmap);
+ if (remainder)
+ *remainder = move_sum;
+ return 0;
+}
+
+static inline int __lttng_counter_add_percpu(const struct lib_counter_config *config,
+ struct lib_counter *counter,
+ const size_t *dimension_indexes, int64_t v)
+{
+ int64_t move_sum;
+ int ret;
+
+ ret = __lttng_counter_add(config, COUNTER_ALLOC_PER_CPU, config->sync,
+ counter, dimension_indexes, v, &move_sum);
+ if (caa_unlikely(ret))
+ return ret;
+ if (caa_unlikely(move_sum))
+ return __lttng_counter_add(config, COUNTER_ALLOC_GLOBAL, COUNTER_SYNC_GLOBAL,
+ counter, dimension_indexes, move_sum, NULL);
+ return 0;
+}
+
+static inline int __lttng_counter_add_global(const struct lib_counter_config *config,
+ struct lib_counter *counter,
+ const size_t *dimension_indexes, int64_t v)
+{
+ return __lttng_counter_add(config, COUNTER_ALLOC_GLOBAL, config->sync, counter,
+ dimension_indexes, v, NULL);
+}
+
+static inline int lttng_counter_add(const struct lib_counter_config *config,
+ struct lib_counter *counter,
+ const size_t *dimension_indexes, int64_t v)
+{
+ switch (config->alloc) {
+ case COUNTER_ALLOC_PER_CPU: /* Fallthrough */
+ case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL:
+ return __lttng_counter_add_percpu(config, counter, dimension_indexes, v);
+ case COUNTER_ALLOC_GLOBAL:
+ return __lttng_counter_add_global(config, counter, dimension_indexes, v);
+ default:
+ return -EINVAL;
+ }
+}
+
+static inline int lttng_counter_inc(const struct lib_counter_config *config,
+ struct lib_counter *counter,
+ const size_t *dimension_indexes)
+{
+ return lttng_counter_add(config, counter, dimension_indexes, 1);
+}
+
+static inline int lttng_counter_dec(const struct lib_counter_config *config,
+ struct lib_counter *counter,
+ const size_t *dimension_indexes)
+{
+ return lttng_counter_add(config, counter, dimension_indexes, -1);
+}
+
+#endif /* _LTTNG_COUNTER_API_H */
projects / deliverable / lttng-ust.git / blobdiff